Terminal structure.



INVENTOR D Attys C. W. DAVIS.

TERWNAL STRUCTURE.

APPLICATION FILED IAN. Il, 1913. 1,159,655, Patented Nov. 9, 1915.

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CHARLES W. DAVIS, OF EDGEWORTH, PENNSYLVANIA, ASSIGNOR T0 STANDARD UNDERGROUND CABLE COMPANY, OF PITTSBURGHLPENNSYLVANIA, A. CORPO- RATION OF PENNSYLVANIA.

TERMINAL STRUCTURE.

Specification of Letters Patent.

Patented Nov. 9, 1915.

T0 @ZZ ywhom/15 'may concern:

Be it known that I, CHARLES W. Davis, residing at Edgeworth, in the county of Allegheny and State of Pennsylvania., a citizen of the United States, have invented or discovered certain new and useful nr provenients in` Terminal Structures, of

which improvements the following is a specification.

rThe object of my present invention 1s to provide a terminal structure for electrical cables, which will be moisture proof, which may be easily installed, and of which the electrical connections between conducting elements will be unimpaired by the different heat conditions of service.

In the accompanying drawing l have illustrated an embodiment of my invention, the figure showing two terminals, one in elevation and one in longitudinal section, each terminal being connected to a conductor of a multiple conductor cable.

In the illustrative embodiment of my invention a two-part thimble is provided, consisting of a cable receiving bell 1 adapted to be secured toa cable as by a wiped soldered joint. and a terminal receiving fork 2 provided with three terminal receiving sleevelike projections 3. rfhese thimble parts may have screw-thread attachments to each other as shown. A sleeve of insulating material such as porcelain or glass, is secured to the thimble projections preferably by first securing an exteriorly threaded ring .3 to the sleeve. The specific shape of said sleeve may be such as to best meet the requirements of the installation for which it is intended. As shown herein, the sleeve is provided with petticoats 6, 7. The passageway or opening S through the sleeve is contracted near its outer end so as to form a shoulder 9, and the outer end of the sleeve is narrowed down to form an outwardly extended ring 10. A conducting stem extends into the sleeve l, and preferably consists of a rod 11, screw-threaded at its outer end, and provided integrally with a cup-shaped portion 12 at its inner end adapted to be sweated upon a cable conductor 123. A nut 1t, preferably of conducting material, is threaded upon said conducting element- 11. 'lhe lower end of said nut is provided with a hood 15, which ineloses or overlaps the outer end or ring 10 of the insulation sleeve a; and said nut is provided with a recess adapted to receive an annulus of packing or gasket 16. A conducting lug 17, suitably formed to make connection to an aerial line, loosely surrounds the threaded portion of the conducting stem 11, and a closed cap or cap nut 18, preferably of conducting material` is threaded upon the end of said conducting stem, and clamps said lug 1T into electrical contact with the adjacent surfaces of said cap-nut and the said hood-nut. And, in order to prevent moisture from gaining entrance to the stem 11, the contacting faces of said nuts and lug are suitably dovetailed. To such an end recesses 19 and 20 are formed on the lower surface of the lug 17 and cap 1S, respectively, such recesses being adapted to receive annular ridges 21 and Q2 formed on the upper surfaces of the hood-nut 14 and lug 17, respectively.

ln the practice of my invention it is essential that one or bot-h of the nuts 11 and 18 be formed of electrical conducting material, and that the said nuts be so tightened upon the stem 11 that their threads will be kept in Contact with the threads of t-he stem. By such a construction it will be seen that, when the stem 11 is elongated by reason of its beingvheated by the currentl passing through it, such elongation will not cause the stem to move with relation to the nuts. lVhile it is essential only that one of said nuts be of conducting material, it will be seen that better electrical conductivity may be had in this particular embodiment of my invention by making both of conducting material. lVhen thus constructed the electrical current will iow from the cable conductor 13 throuoh the stem l2, 11, nuts 1l and 1S, and lug 1': to an aerial line connected thereto.' ln flowing from the. stem 11 to the nuts 14 and 1S, the current passes through the threads of said members; and in tlowing from said nuts to the lug 1T, the current passes through the contacting faces thereof.

ln making a connection between a cable conductor and an aerial line by means of my improved terminal structure. the cable shcatlris cut back and the stein 1l, l2 is sweated upon the end of the bared conductor 155. '.lhe stein-provided conductor is then threaded through the thimble, 1, Q, which in turn is secured to the cable by a wiped joint, and the sleeve of insulation l is I j ment with the shoulder 9.

slipped over said conductor and stem and secured into place in the thimble projection V3. Thehood-'nut 14 is then secured upon the stem l1, and tightened so that the packing bears upon the top ofthe ring 1 0 and the stem 11 is drawn outwardly until the enlarged portion 12 thereof is in engage- The lug 17, which may be previously connected to an aerial-line is then slipped over the threaded end of the stem 12 and the cap nut 1S is screwed down so as to cla-mp said lug in place.

Since, in the installationof the terminal,

the sleeve 4L is slipped over the stem 11, 12,

and conductor 13, after electrical connection has been made between them, the thimble projections may be made much shorter than is required when the sleeve is'slipped over the conductor Aand electrical connection made to a conducting element thereafter. The saving in material and space by the use of such relatively short thimble projections is of considerable importance in installations where the terminals are used with multiple conductor cables, as shown herein.

In case it becomes desirable for testing or other purposes .to break the electrical. connection between an aerial and the conductor 13, the same may be done by removing the cap-nut 18 and lifting the lug 17 off the stem 11. Thecap may then be quickly replaced to prevent moisture from entering the terminal structure, and it will be seen that when the cap is thus replaced the recess 19 therein will receive the ridge 21 of the disk 14.

I claim herein as my invention:

In a vertically disposed terminal structure for the ends of electrical conductor cables, the combination witha thimble adapted to be connected to a cable sheath, a conducting stem adapted to be electrically connected at its inner end to a cable conductor and screwthreaded at its outer end, an upwardly-extending tubular insulator secured to the thimble and surrounding the lower end of said stem, said insulator being vapplicable to the thimble after said stem hasrbeen connected to a cable conductor, and a hooded nut screwed upon the stem and inclosing the .upper end of said insulator; of a cap nut screwed upon and inclosing the outer end of said stem, a conducting collar surrounding said stem between the adjacent faces of the nuts and in contact therewith, the contacting faces of said nuts and collar being provided with outwardly-extending, dove-tail ing ridges and grooves, and said cap nut being screwed tightly upon said collar thereby keeping the threads of each nut in electrical contact with those of said stem.

In testimony whereof I have hereunto set my hand.

CHARLES W. DAVIS.

Witnesses: V

ARTHUR A. ANDERSON, RALPH B. WILCOX. 

